Rotary Paddle Switches Applied in Integrated Sludge Incineration System

An Anhui sewage treatment plant builds a 100 t / D circulating fluidized bed integrated sludge incineration project, and provides the best solution for the final disposal of urban sludge. The processes of the integrated sludge incineration system mainly include drying system, incineration system and flue gas purification system. The drying system contains dryer, fine-powder separator, condenser, gas-water separator and circulating fan.

Level switches are essentials to control and monitor the fine powder levels in fine-powder separator to ensure the efficiency of the fine-powder separator and plays an important role in the continuous operation of the entire system.

RF admittance level switches were used by the client with inaccurate detections and frequent false alarms. Due to the high powdery dust and fine particle size, as well as the unstable dielectric constant and conductivity of medium (the powder particles after sludge drying), RF admittance level switches were not able to measure reliably in such situation.

Instead of RF admittance level switch, the client tested Jiwei Spin-11 Rotary Paddle Switches for trials. In Spin-11 Rotary Paddle Switch series of products，micro motor, through a clutch, drives the rotation of a transmission shaft on which a paddle is assembled. When the spinning paddle is not contacted with measured material, the motor is in normal rotation; when the paddle is covered by measured material, the motor stops rotating and its power is switched off automatically. At the same time, a switching signal is generated by a detection device to control the process of material transport /delivery. In comparison with other similar products in the market, Jiwei Spin-11 Rotary Paddle Switch has the following advantages:

●　Purchased high quality well-known brand motors and micro switches as its key parts.

●　Dual bearing design, with stable operation and long life time in service.

●　Integrated design and anti-loose mechanical control mechanism, easy for parts replacement and maintenance.

●　Made of 304/316L stainless steel.

●　IP65 Ingress Protection rating.

The performance and indexes of Spin-11 Rotary Paddle Switch fully meet the measurement requirements of client, and so far all Spin-11s are monitoring the measurement of both high and low positions of the fine-powder separator in the integrated sludge incineration system without any false alarms or defects.